Many attempts have been made over the years to produce cutting apparatus that could effectively cut relatively long lengths of tubing into desired shorter lengths. One approach has involved the use of a cutting or pinch roll operating on the same principle as the pipe cutter utilized by plumbers. Another approach has involved the use of a screw machine in which a stationary knife bears against a bar that is rotated. Another approach has involved the use of two aperture dies, initially aligned, one of which is displaced relative to the other at right angles to the axis of the stock to shear the tubing. Another approach has involved the use of a screw type machine in which the tubing is maintained stationary and the knifes are rotated to cut the tubing. All of these prior art devices have the disadvantage that a burr or rough edge or other distortion is formed along the inner periphery of the cut.
In an attempt to avoid such burrs or rough edges, tube cutting systems have been devised in which a mandrel is located down the center of the tubing and fucntions during the cutting operation to minimize distortion along the inner periphery of the cut. While these mandrel systems have in general eliminated or at least alleviated the rough edge along the inner periphery of the cut, they have required an extremely complicated overall cutting apparatus to accommodate the mandrel function and/or have resulted in a significant slowing of the rate of production of tubing by the tube cutting apparatus.